1. Field of the Invention
The present invention can be classified to air traffic control, and particularly to a tandem-cycle target/track assignment method in combined radar/ADS surveillance environment.
2. Description of the Related Art
Future radar/ADS combined surveillance environment includes the following facilities: primary radar, secondary radar, Automatic Dependent Surveillance-Addressing (ADS-A), and Automatic Dependent Surveillance-Broadcast (ADS-B). These facilities"" report rates are quite different. For example, ADS-B broadcasts every second and, on the other hand, ADS-A sends reports every 15 to 30 minutes, on average. To eliminate problems which might come with the various report rates, current air traffic control system needs a new target/track assignment method to get the latest surveillance information of an aircraft in real time.
In the present invention, a tandem-cycle target/track assignment method is proposed to satisfy this requirement.
The object of the present invention is to provide a tandem-cycle target/track assignment method in combined radar/ADS surveillance environment so that an air traffic control system can get the latest surveillance information of aircrafts in real time.
The method contains the following steps; (A) determine whether the system should run a batch process. If not, go to (B); otherwise go to (G). (B) filter out improper targets; (C) according to system track""s position, velocity, etc., select candidate tracks which might correlate with the reported target; (D) according to the candidate track""s type and correlation conditions, further filter candidate tracks selected in (C) and calculate remaining tracks"" likelihood values while correlating them with the reported target. Save all likelihood values of track-target pairs for later processing in (G). If no candidate track can be found, initialize a new track using the reported target; (E) determine when should the system update tracks. If in sequential process, go to (F); otherwise go to (G). (F) select a system track which likelihood value is the highest, update it with the reported target, and then go to (A). (G) If it""s time to run a batch process, use the auction algorithm to select best track-target pairs and update system tracks with their best targets. Then, go to (A).
The various objects and advantages of the present invention will be readily understood in the following detailed description.